1. Field of the Invention
The present invention generally relates to systems and methods for optical imaging and, more specifically, to providing fast (non-scanning) optical microscopy method and apparatus for selectively viewing various object features, including features buried under non-transparent material.
2. Description of the Related Art
Viewing of object features buried under “nontransparent materials” represents a serious technical challenge, especially when the optical vision system must be capable of generating real time live images of the object and the object features do not transmit light. Scanning is not an acceptable solution in such vision systems and back light illumination cannot be used because the object features themselves do not transmit backlight. Moreover, the use of an illuminating light with a wavelength located within the material transparency window may sometimes not be practical due to cost considerations, especially if the material transparency window is outside of the wavelength range of visible light. As would be appreciated by persons of skill in the art, using ultraviolet or infrared sources of light for illumination of the nontransparent object together with imaging sensors having sensitivity in the corresponding wavelength ranges considerably increases the overall cost of the optical inspection system and, therefore, is undesirable. In addition, the use of infrared illumination light sources is disfavored because the optical resolution of the imaging system decreases with the increase of the wavelength of the illuminating light.
In other applications it is desirable to have a vision system that would emphasize certain features of the object and de-emphasize others. For example, in many applications the surface texture of the object is not as important as features appearing on the object's surface.